Google Professional-Cloud-Network-Engineer Exam With Confidence Using Practice Dumps

For GKE pods that need to egress directly to the internet for most of their communications, the most cost-efficient and straightforward approach is to deploy a GKE cluster with public cluster nodes. Public nodes have external IP addresses, allowing pods to directly reach the internet. This eliminates the need for additional services like Cloud NAT or Secure Web Proxy for outbound internet access, which would incur extra costs and management overhead.

Exact Extract:

"Public clusters have nodes with external IP addresses, allowing them to directly initiate connections to the internet. This is the simplest configuration for clusters that require direct internet egress for their workloads."

"When using public clusters, Cloud NAT is not required for outbound internet connectivity from the nodes or pods, as they can use their external IP addresses. This can reduce operational overhead and cost compared to private clusters that need NAT."Reference: Google Kubernetes Engine Documentation - Cluster network configuration, Public clusters vs Private clusters

To determine the Pod per node CIDR range, you need to calculate how many IP addresses are required for each node, and then choose the smallest CIDR range that can accommodate that number. A CIDR range of /n means that there are 2^(32-n) IP addresses available in that range. For example, a /24 range has 2^(32-24) = 256 IP addresses.

According to the question, the application team requires a minimum of 60 Pods per node and a maximum of 100 Pods per node. Therefore, you need to choose a CIDR range that can provide at least 100 IP addresses per node, but not more than necessary. A /25 range has 2^(32-25) = 128 IP addresses, which is enough for 100 Pods per node. A /26 range has 2^(32-26) = 64 IP addresses, which is not enough for 60 Pods per node. A /24 range has 256 IP addresses, which is more than needed and wastes IP address space. A /28 range has 2^(32-28) = 16 IP addresses, which is far too small for any node.

Therefore, the best option is B. /25. This is also consistent with the Google Kubernetes Engine documentation, which states that each node is allocated a /24 range of IP addresses for Pods by default, but the maximum number of Pods per node is 1101. This means that there are approximately twice as many available IP addresses as possible Pods, which is similar to the ratio of 128 to 100 in the /25 range.

1: Configure maximum Pods per node | Google Kubernetes Engine (GKE) | Google Cloud